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The dairy industry accounts for 9–14% of East Africa's agricultural gross development product. Due to lack of milk cooling facilities, dairy farmers in areas without access to reliable grid electricity face problems of high milk spoilage and limited access to formal markets, which limits their income and standard of living. This article examines the economic viability for a number of configurations of off-grid solar, wind, biomass and biogas based milk-cooling systems serving a community in Tanzania. Key risk factors having the greatest impact on system viability are identified and a stochastic approach, by means of a Monte Carlo simulation is employed to determine the risk-adjusted economic performance of the project. The results indicate that biogas based systems offer the most viable option, with an internal rate of return of around 25%, a net present value of around $9000 and a projected increase in farmers' monthly income of at least 78%. Despite specific risk factors, the 300-L cooling system had an 82% probability of a positive net present value. However, larger system cooling capacities have a significant likelihood of a financial loss. Consequently, risk mitigation strategies designed to increase the probability of economic success are proposed.

The lack of modern electricity supply has been a major impediment to proper functioning of the healthcare centers in the rural areas, contributing to high maternal and child mortality rates in a country. Therefore, this study focuses on how to address the identified problem so that the healthcare centers or clinics in the remote areas can provide timely delivery of medical services for the concerned people. This paper, then, presents the analysis of stand-alone hybrid renewable energy systems for basic healthcare services in the rural areas, where there is no grid energy supply or the supply from the existing grid is erratic and unreliable. One major factor that informs the selection of the hybrid energy system in this study is that it promises high reliability compared to a single energy system. The research presents a statistical analysis of the potential of wind and solar energies for a selected rural locations in Nigeria based on the available long-term hourly and daily meteorological data. It employs an optimal technical and economic design and sizing of hybrid electrical power systems’ components such as the wind, PV, battery and inverter systems, using the hybrid optimisation software (HOMER). Results show that Sokoto and Jos sites exist in the high wind potential regions, while the remaining sites are only suitable for small wind applications. Values obtained for global radiation show that all the sites enjoy considerable solar energy potential suitable for varying degree of solar energy applications. PV/wind/diesel/battery hybrid system configuration is considered optimum for rural health center at Iseyin, Sokoto, Maiduguri, Jos and Enugu, while hybrid systems involving PV/diesel/battery is considered ideal for Port-Harcourt, due to the quality of renewable energy potential. Hence, it was concluded that, the abundance of wind and solar resources in the country create an ideal environment for inclusion of renewable energy systems in the design and implementation of standalone power supply systems to improve rural healthcare delivery.

Energy poverty in the majority of the rural households in Kenya is a threat to economic and social development; hence the availability of an affordable and reliable domestic energy source is important. This study investigated: the potential resources for biogas for cooking, suitable anaerobic digesters that could be deployed in rural households, and also the viability of a small community biogas business model. Conservative estimates of the business model parameters and sensitivity analysis revealed that there was adequate biogas potential in central and western Kenya while water scarcity affected other regions' opportunities. Cattle manure was the predominant feedstock, although crop waste has possibilities to contribute to biogas production. Economically and technically, the inflatable tubular digester was found to be the most suitable type for biogas production in rural Kenya. Discounted cash flow analysis of the business model proved a profitable business to supply an affordable household energy at 0.55€/Kg of biogas, with projected household savings of 249€ annually. Labor cost was found to have high significance on the feasibility of the business model which was also sensitive to changes in biogas revenues. Kenya's rural areas have significant biogas potential to reduce energy poverty, generate income and aid social development.

Access to reliable electricity eludes many poor rural Afghan communities despite plentiful renewable resources. Micro-generation seems particularly well suited to Afghanistan’s mountainous, decentralised society but even with substantial investment since 2001 it has not lived up to expectations. Recognising the causes are likely to dwell in the human (rather than technical) domain, this study takes a qualitative, soft systems approach to deriving and validating the necessary conditions that might improve the success rate of micro-generation projects in enabling sustainable economic development. It acknowledges the governance limitations inherent in fragile states and the significance of the community as the most stable element of society, putting the latter at the centre of its thinking. Those conditions identified as critical are summarised as: a holistic approach that sees micro-generation as a component of broader economic development; an environment safe enough for project build and operation, and for the markets necessary for wealth creation; and external support to build community capacity to fund and maintain schemes through-life. These conditions are likely to have relevance for other fragile states; the next step is to develop them in the field before deployment as part of a comprehensive approach to poverty alleviation in Afghanistan and similar states.

Demand side management is traditionally concerned with adjusting the load to meet generation to assist with stability, ratings or other constraints. However, in many countries, load outstrips generation and instead of managing the load, shedding the load is more common. This paper looks at a portion of the Libyan grid system which suffers from daily load shedding and explores if AI concepts can be used to intelligently manage the shedding of this load so that it is unnoticeable to consumers.

Greenhouse gas (GHG) emissions from dairy farms are significant contributors to global warming. However, much of the published work on GHG reduction is focused on either methane (CH4) or nitrous oxide (N2O), with few, if any, considering the interactions that changes to farming systems can have on both gases. This paper takes the raw data from a year of activity on a 300-cow commercial dairy farm in Northern Ireland to more accurately quantify GHG sources by use of a simple predictive model based on IPCC methodology. Differing herd management policies are examined together with the impact of integrating anaerobic digestion (AD) into each farming system. Whilst significant success can be predicted in capturing CH4 and carbon dioxide (CO2) as biogas and preventing N2O emissions, gains made can be lost in a subsequent process, negating some or all of the advantage. The process of extracting value from the captured resource is discussed in light of current farm parameters together with indications of other potential revenue streams. However, this study has concluded that despite the significant potential for GHG reduction, there is little incentive for widespread adoption of manure-based farm-scale AD in the UK at this time.

This paper presents the technical validation of a novel, low-complexity alternative based on the inclusion of a patented (IEPI-MU-2016-185) packed bed for improving the performance of remote, small-scale gasification facilities. This study was carried out in an updraft, atmospheric-pressure gasifier, outfitted with a syngas reflux line, air and oxygen feed, and an upper packed-bed coupled to the gasification unit to improve the syngas quality by catalytic treatment and CO2 adsorption. The experimental facility is located in the rural community San Pedro del Laurel, Ecuador. Gasification experiments, with and without packed material in the upper chamber, were performed to assess its effect on the syngas quality. The assessment revealed that the packed material increases the carbon monoxide (CO) content in the syngas outlet stream while carbon dioxide (CO2) was reduced. This option appears to be a suitable and low-complexity alternative for enhancing the content of energy vectors of syngas in gasification at atmospheric pressure since CO/CO2 ratios of 5.18 and 3.27 were achieved against reported values of 2.46 and 0.94 for operations which did not include the addition of packed material. It is concluded that the upper packed-bed is an active element able to modify syngas characteristics since CO2 content was reduced.

Bioethanol is a renewable energy source produced from the resources which can be easily replenished. The bioethanol production through fermentation may provide an economically competitive source of energy by its incorporation into gasoline. Production of bioethanol from waste food crops like potatoes could be the better substrate, and the waste produced is also biodegradable. Lack of storage facilities and postharvest losses make potato a promising crop which can be used for production of ethanol. Moreover, the conversion of potato starch into glucose by bakhar is more cost-effective, and fermentation with baker’s yeast Saccharomyces cerevisiae yields maximum amount of ethanol. This process of production of ethanol from waste potato would be promising and economically effective for the production of biofuel, called bioethanol.